Skip to Main content Skip to Navigation
Theses

Etude de la commande optimale en Optique Adaptative et Optique Adaptative Multi-Conjuguée, validation numérique et
expérimentale.

Abstract : Astronomical imaging from ground-based telescopes is strongly degraded by the
atmospheric turbulence. Adaptive Optics (AO) provides real time correction
of the turbulence effects, increasing angular resolution.
However, technological and fundamental limitations restrict the performance of
AO. High dynamic AO (or eXtreme AO - XAO) and wide field of view AO
(Multi-Conjugate AO - MCAO) have been proposed to overcome these effects. But
control laws classically used in AO are unsuited for these more complex
applications.

The goal of this thesis is to investigate an optimal control law, in terms of
minimum variance, on both theoretical and experimental grounds. This Linear
Quadratic Gaussian (LQG) type
control law is analysed and its implementation constraints are evaluated in
terms of algorithms and models. We also propose to deal with additive
perturbations such as vibrations, present on most systems. Finally, we present
the first laboratory validation of this kind of control law in AO and on a
simplified MCAO system. A huge gain in performance is brought by our control
law compared to more classical ones. These results are comforted by numerical
simulations. Performance of the LQG control on VLT-like MCAO systems is then
estimated thanks to numerical simulation. All these results confirm the
significant gain brought by our approach and its flexibility to handle both
complex wave-front sensing geometries and optimisation of the correction in
specific fields of interest.
Complete list of metadatas

Cited literature [147 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00134154
Contributor : Cyril Petit <>
Submitted on : Thursday, March 1, 2007 - 9:04:10 AM
Last modification on : Friday, June 26, 2020 - 2:00:02 PM
Long-term archiving on: : Wednesday, April 7, 2010 - 2:53:46 AM

Identifiers

  • HAL Id : tel-00134154, version 1

Collections

Citation

Cyril Petit. Etude de la commande optimale en Optique Adaptative et Optique Adaptative Multi-Conjuguée, validation numérique et
expérimentale.. Astrophysique [astro-ph]. Université Paris-Nord - Paris XIII, 2006. Français. ⟨tel-00134154⟩

Share

Metrics

Record views

498

Files downloads

1261